/*
 * Copyright (c) 1988 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*
 * High level routines dealing with the output to the screen.
 */

#include <stdio.h>
#include <string.h>
#include <less.h>

int errmsgs;    /* Count of messages displayed by error() */

extern int sigs;
extern int sc_width, sc_height;
extern int ul_width, ue_width;
extern int so_width, se_width;
extern int bo_width, be_width;
extern int tabstop;
extern int screen_trashed;
extern int any_display;
extern char *line;

/* display the line which is in the line buffer. */
put_line()
{
        register char *p;
        register int c;
        register int column;
        extern int auto_wrap, ignaw;

        if (sigs)
        {
                /*
                 * Don't output if a signal is pending.
                 */
                screen_trashed = 1;
                return;
        }

        if (line == NULL)
                line = "";

        column = 0;
        for (p = line;  *p != '\0';  p++)
        {
                switch (c = *p)
                {
                case UL_CHAR:
                        ul_enter();
                        column += ul_width; /* +1; XXX */
                        break;
                case UE_CHAR:
                        ul_exit();
                        column += ue_width;
                        break;
                case BO_CHAR:
                        bo_enter();
                        column += bo_width; /*  +1; XXX */
                        break;
                case BE_CHAR:
                        bo_exit();
                        column += be_width;
                        break;
                case '\t':
                        do
                        {
                                putchr(' ');
                                column++;
                        } while ((column % tabstop) != 0);
                        break;
                case '\b':
                        putbs();
                        column--;
                        break;
                default:
                        if (c & 0200)
                        {
                                /*
                                 * Control characters arrive here as the
                                 * normal character [CARAT_CHAR(c)] with
                                 * the 0200 bit set.  See pappend().
                                 */
                                putchr('^');
                                putchr(c & 0177);
                                column += 2;
                        } else
                        {
                                putchr(c);
                                column++;
                        }
                }
        }
        if (column < sc_width || !auto_wrap || ignaw)
                putchr('\n');
}

static char obuf[1024];
static char *ob = obuf;

/*
 * Flush buffered output.
 */
flush()
{
        register int n;

        n = ob - obuf;
        if (n == 0)
                return;
        if (write(1, obuf, n) != n)
                screen_trashed = 1;
        ob = obuf;
}

/*
 * Purge any pending output.
 */
purge()
{

        ob = obuf;
}

/*
 * Output a character.
 */
putchr(c)
        int c;
{
        if (ob >= &obuf[sizeof(obuf)])
                flush();
        *ob++ = c;
}

/*
 * Output a string.
 */
putstr(s)
        register char *s;
{
        while (*s != '\0')
                putchr(*s++);
}

int cmdstack;
static char return_to_continue[] = "(press RETURN)";

/*
 * Output a message in the lower left corner of the screen
 * and wait for carriage return.
 */
error(s)
        char *s;
{
        int ch;

        ++errmsgs;
        if (!any_display) {
                /*
                 * Nothing has been displayed yet.  Output this message on
                 * error output (file descriptor 2) and don't wait for a
                 * keystroke to continue.
                 *
                 * This has the desirable effect of producing all error
                 * messages on error output if standard output is directed
                 * to a file.  It also does the same if we never produce
                 * any real output; for example, if the input file(s) cannot
                 * be opened.  If we do eventually produce output, code in
                 * edit() makes sure these messages can be seen before they
                 * are overwritten or scrolled away.
                 */
                if (s != NULL) {
                        (void)write(2, s, strlen(s));
                        (void)write(2, "\n", 1);
                }
                return;
        }

        lower_left();
        clear_eol();
        so_enter();
        if (s != NULL) {
                putstr(s);
                putstr("  ");
        }
        putstr(return_to_continue);
        so_exit();

        if ((ch = getchr()) != '\n') {
                if (ch == 'q')
                        quit();
                cmdstack = ch;
        }
        lower_left();

        if ((s != NULL ? strlen(s) : 0) + sizeof(return_to_continue) + 
                so_width + se_width + 1 > sc_width)
                /*
                 * Printing the message has probably scrolled the screen.
                 * {{ Unless the terminal doesn't have auto margins,
                 *    in which case we just hammered on the right margin. }}
                 */
                /* repaint(); */
                screen_trashed = 1;     /* XXX */
        flush();
}

static char intr_to_abort[] = "... (interrupt to abort)";

ierror(s)
        char *s;
{
        lower_left();
        clear_eol();
        so_enter();
        putstr(s);
        putstr(intr_to_abort);
        so_exit();
        flush();
}
